The present invention relates to an ostomy bag and to an improved coupling for joining an ostomy bag to a pad, label or surgical dressing.
Ostomy bags are used to collect waste from patients with a stoma resulting from an ileostomy, colostomy or similar surgical procedure. An ostomy bag comprises two thin film walls which are sealed along their periphery by heat welding or the like. One wall has an aperture to receive the stoma.
The ostomy bag is secured to the patient by attaching it to an adhesive backed label through which an opening can be made in the center to receive the stoma. The adhesive backed label can be worn comfortably for extended periods of time which are longer than the time normally required for the bag to fill to capacity with waste material. Examples of acceptable adhesive backed labels are described in U.S. Pat. No. 3,339,546 by Chen.
It is desirable when replacing the filled ostomy bag with an empty one that the ostomy bag be removed and replaced without requiring that the adhesive backed label be removed. This is accomplished through the use of a coupler which comprises a pair of plastic rings, one of which forms a channel or groove and the other, a projection or rib for frictional engagement with the channel or groove. Each ring defines an aperture for receiving a stoma therethrough. One ring, usually the one with the channel, is attached to the bag with its aperture aligned with the aperature in the bag, while the other ring is attached to the label on a surface opposite the adhesive, also with its aperture aligned with the opening in the bag when the two rings are coupled together. Using this coupling arrangement the bag and label can be connected around the stoma by aligning the coupler rings and pressing them together to cause frictional engagement. A coupler suitable for this application is described in Great Britain Patent specification No. 1,571,657, published July 16, 1980.
The coupling rings are coupled together by applying a significant force on the bag to press the rings together. Where one of the coupling rings is mounted directly to the surface of the label, a great amount of the force is absorbed by the sensitive skin beneath the label. In the prior art to reduce the force applied to the skin, an outwardly extending flange portion of the ring to be attached to the label is attached along a portion of its bottom surface to an outer edge portion of a thin annular web of flexible thermoplastic material. The web extends inwardly from the flange portion and the inner edge portion of the web is attached to the label. This arrangement allows a user of the ostomy bag to insert the user's fingers between the web and the label and press the coupling rings together to attach the ostomy bag to the label. The fingers then absorb at least some of the applied force. See U.S. Pat. No. 4,419,100. This patent further discloses that the inner edge of the web may be attached to an annular mounting collar which in turn is attached to the faceplate to reinforce it in the area about the opening which receives the stoma.
In European Patent application No. Al0098718 published Jan. 18, 1984, a ring mounting means for mounting a coupling ring to the label is disclosed which includes a first section adapted to be affixed to the surface of the label and an accordion-like section positioned between the first section and a second section to be attached to the coupling ring. The accordion-like sections facilitate further displacement of the coupling ring from the label over the single web of thermoplastic material described above so that the coupling rings can be engaged and the forces diverted from the skin around the stoma by permitting the mounting means to expand when the fingers are inserted between the coupling ring and the label. Accordion-like sections with a single fold and triple folds are explicitly disclosed. The single fold is higher to provide the same amount of movement away from the label as the triple fold design without moving the mounting ring away from the attachment but has the disadvantage of providing a higher profile. Also, the single fold design places more stress on the single hinge at the fold sometimes resulting in cracking at the fold.
When designing the mounting means for attaching a coupling ring such as the coupling rings described above it is desirable to provide maximum flexibility, low profile, and comfort of use, while insuring adequate support for the ostomy bag during use and secure and reliable attachment of the mounting means to the label. At the same time it is desirable to maximize the area of the opening defined by attachment of the mounting means to the label for receiving the largest size stoma possible.